Volume 8, number 4
In Search of Planet X
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(Planetary Society members only)
4 The Saying of Science: Jonathan Eberhart discusses how science often leads along converging successions of questions rather than from answer to specific answer.
6 Planet X: Fact or Fiction? John Anderson looks at the evidence for a tenth planet in our solar system.
10 Humans to Mars: The Mission That NASA Did Not Fly: Edward Ezell examines why we haven't yet sent humans to Mars.
3 Members' Dialogue SETI, expanding beyond Earth, and remembering a son.
16 World Watch NASA appropriation, CRAF and Cassini, and Russia's Phobos mission.
17 News & Reviews Heavenly chaos; struggling U.S. space science.
18 Society Notes Teaching the teachers, the Caltech Balloon Symposium, and dolphin communication.
28 Q&A How does an icy body in the Oort cloud "fall into" our solar system and become a comet?